KENALOG-10
Clinical safety rating: caution
Comprehensive clinical and safety monograph for KENALOG-10 (KENALOG-10).
Triamcinolone acetonide is a synthetic corticosteroid with anti-inflammatory, immunosuppressive, and antiproliferative actions. It binds to glucocorticoid receptors, modulating gene expression to inhibit phospholipase A2, reduce prostaglandin and leukotriene synthesis, and suppress cytokine production (e.g., IL-1, IL-2, TNF-alpha). It also stabilizes lysosomal membranes and inhibits fibroblast proliferation.
| Metabolism | Primarily hepatic via CYP3A4. Triamcinolone acetonide is metabolized to inactive metabolites, mainly 6β-hydroxytriamcinolone acetonide. Less than 1% excreted unchanged in urine. |
| Excretion | Primarily hepatic metabolism (~80%) followed by renal excretion of inactive metabolites (glucuronide and sulfate conjugates). Unchanged triamcinolone acetonide accounts for <5% of urinary recovery. Biliary/fecal excretion is minor. |
| Half-life | Terminal elimination half-life is approximately 2–5 hours for triamcinolone acetonide. However, the duration of action is prolonged due to the crystalline suspension's slow dissolution from the injection site, resulting in a prolonged residence time and effects lasting weeks. The plasma half-life primarily reflects systemic clearance after absorption. |
| Protein binding | Approximately 68–79% bound to plasma proteins, primarily albumin and corticosteroid-binding globulin (CBG). |
| Volume of Distribution | Apparent volume of distribution is approximately 0.2–0.5 L/kg. This low Vd reflects limited extravascular distribution and high protein binding. |
| Bioavailability | Intramuscular administration: 100% bioavailable (by design, as it is a depot formulation). Oral: Not applicable (not available). Intra-articular: Bioavailability is essentially 100% at the local site, but systemic absorption is limited; peak plasma concentrations are lower than after IM injection due to slow release. |
| Onset of Action | Intra-articular/soft tissue injection: Onset of anti-inflammatory effect occurs within 24–48 hours, though pain relief may begin within hours. Intramuscular administration: Onset is within 1–2 hours for systemic effects. |
| Duration of Action | Intra-articular injection: Duration of symptomatic relief typically lasts 1–2 weeks for small joints and up to 3–4 weeks for larger joints (e.g., knee). Intramuscular depot: Systemic glucocorticoid effects may persist for 2–3 weeks due to slow release. The duration is variable and depends on dose, injection site, and individual factors. |
| Molecular Weight | 434.5 |
Intra-articular, intrabursal, or soft tissue injection: 10-40 mg (0.25-1 mL of 10 mg/mL) for large joints; 10 mg (0.25 mL) for small joints; repeat every 3-4 weeks if needed. Intralesional: 10-40 mg (0.25-1 mL) per lesion; maximum 1 mL per injection site; repeat every 1-2 weeks.
| Dosage form | INJECTABLE |
| Renal impairment | No specific GFR-based dose adjustment required; use caution in severe renal impairment due to potential systemic effects. |
| Liver impairment | No specific Child-Pugh-based dose adjustment; use caution in severe hepatic impairment due to potential corticosteroid-related adverse effects. |
| Pediatric use | Intra-articular: 5-20 mg for large joints, 2.5-10 mg for small joints; intralesional: 2.5-10 mg per lesion; dose based on body surface area (BSA) and severity; not recommended for children under 12 unless directed by specialist. |
| Geriatric use | Initiate at lower end of dosing range (e.g., 10-20 mg intra-articular); monitor for increased susceptibility to corticosteroid side effects, including osteoporosis, hyperglycemia, and immunosuppression; avoid repeated injections in weight-bearing joints. |
| 1st trimester | Use only if clearly needed; corticosteroids are teratogenic in animals, but human data limited. Avoid first trimester if possible. |
| 2nd trimester | Use with caution; may cause fetal growth restriction and adrenal suppression. Monitor fetal growth. |
| 3rd trimester | Use with caution; risk of neonatal adrenal suppression and possible low birth weight. Avoid prolonged use near term. |
Clinical note
Comprehensive clinical and safety monograph for KENALOG-10 (KENALOG-10).
| Placental transfer | Crosses placenta; metabolized to active form; fetal exposure correlates with maternal dose. |
| Breastfeeding | Triamcinolone is excreted in breast milk in small amounts. Single doses likely safe, but high doses or prolonged use may cause adrenal suppression in infant. Monitor infant for growth and development. |
■ FDA Black Box Warning
No FDA boxed warning specific to KENALOG-10; however, corticosteroids in general have warnings for increased mortality in certain conditions (e.g., systemic fungal infections, cerebral malaria). Avoid live vaccines during therapy.
| Serious Effects |
Systemic fungal infectionHypersensitivity to triamcinolone or any componentLive or live-attenuated vaccine administrationIdiopathic thrombocytopenic purpura (intramuscular use)
| Precautions | Hypothalamic-pituitary-adrenal (HPA) axis suppression with prolonged use or high doses, Increased susceptibility to infections and masking of infection signs, Cushing's syndrome, osteoporosis, avascular necrosis, myopathy, peptic ulcer, pancreatitis, Ophthalmic effects: cataracts, glaucoma, central serous chorioretinopathy, Psychiatric disturbances (euphoria, depression, psychosis), Fetal harm (Pregnancy Category C); use only if benefit outweighs risk |
| Food/Dietary | No specific food interactions. Avoid excessive salt intake, as corticosteroids can cause sodium and water retention. Grapefruit and grapefruit juice may increase systemic absorption if used topically or after injection; limit intake. |
Loading safety data…
| Lactation Rating |
| L2 (probably compatible, but caution) |
| Teratogenic Risk | First trimester: increased risk of cleft palate (odds ratio 1.3-6.7). Second/third trimester: fetal growth restriction, adrenal suppression, hypothalamic-pituitary-adrenal axis suppression. Chronic use: low birth weight, preterm birth. |
| Fetal Monitoring | Maternal: blood pressure, blood glucose, signs of infection, adrenal suppression. Fetal: serial ultrasound for growth restriction (every 4-6 weeks) and amniotic fluid volume. Neonatal: assess for adrenal insufficiency, hypoglycemia, and growth parameters after birth. |
| Fertility Effects | Triamcinolone acetonide may cause menstrual irregularities and suppression of endogenous corticosteroid production, potentially affecting ovulation. No specific human data on impaired fertility; animal studies show no significant impact on fertility. |
| Clinical Pearls | Kenalog-10 (triamcinolone acetonide 10 mg/mL) is a potent corticosteroid for intra-articular, intralesional, or soft tissue injection. Avoid injection into infected joints or unstable joints. Post-injection flare (crystal-induced synovitis) may occur. Do not administer IV, IM, or intradermally. Use caution in patients with diabetes, as it can elevate blood glucose. Limit frequency to every 3-4 weeks per joint to avoid cartilage damage. |
| Patient Advice | Do not exercise or overuse the injected joint for 48 hours after the injection to allow the medication to work. · Report signs of infection (increased pain, redness, swelling, fever) or allergic reactions (rash, difficulty breathing). · You may experience a temporary increase in pain (steroid flare) which usually resolves within 24-48 hours. · Avoid alcohol consumption for at least 24 hours after injection to reduce bleeding risk. · Tell your doctor if you have diabetes, as this medication can increase blood sugar levels. |